Question: What's the first wrong statement in the proof below that $ \triangle CEB \cong \triangle CEF$ $ \; ?$ $ \overline{BC} $ is parallel to $ \overline{DF} $. This diagram is not drawn to scale. $A$ $B$ $C$ $D$ $E$ $F$ Givens $ \angle DBE \cong \angle CFE$ $, \ $ $ \angle BDE \cong \angle ECF$ $, \ $ $ \overline{DE} \cong \overline{CE}$ $, \ $ $ \angle BAC \cong \angle CEF$ $, \ $ $ \overline{AB} \cong \overline{EF}$ $, \ $ and $\ $ $ \angle ABC \cong \angle CFE$ Proof $ \triangle CEF \cong \triangle CAB$ because ASA $ \overline{CF} \cong \overline{BC}$ because corresponding parts of congruent triangles are congruent $ \triangle CEF \cong \triangle DEB$ because AAS $ \overline{EF} \cong \overline{BE}$ because corresponding parts of congruent triangles are congruent $ \triangle CEF \cong \triangle CEB$ because SSS
Explanation: Try going through the proof yourself: write down the givens, and then see if they justify the next step for the reason given. Then do the same thing for the next step, and the next, until you run into something that you can't justify, or you finish the proof. There is no wrong statement in this proof.